Well I may have found some explanation. I'd like some opinions though. It looks like this chart has some answers. From noon to one, I was in a poor reception area as I am everyday at that time. (Lunch in a building with metal roof) Then the reception seems to jump back up to normal. However, around 3, my reception dips again don't when I started to notice the problem with my battery heating up. But I was in an area where I usually have fine reception.
Could it be there was a temporary problem with a local tower? And could that cause the battery heat?